class Boy {
    @speak('zhongwen') //传递参数给language
    run() {
        console.log('i can run')
        console.log('my language is '+this.language) 
    }
    // @speak
    faster() {
        console.log("faster")
        console.log('my language is '+this.language) 
    }
}

function speak(language){
    return function (target, key, description) {
    console.log("target:", target)
    console.log("key:", key)
    console.log("description:", description)

    target.language = language  //target是类,language就是类对象

    return description
}
}

const Luke = new Boy()

// Luke.run()
Luke.faster()